1. Field
The present application relates generally to the operation of data networks, and more particularly, to methods and apparatus for RF channel switching in a multi-frequency network.
2. Background
Data networks, such as wireless communication networks, have to trade off between services customized for a single terminal and services provided to a large number of terminals. For example, the distribution of multimedia content to a large number of resource limited portable devices (subscribers) is a complicated problem. Therefore, it is important for network operators, content retailers, and service providers to have a way to distribute content and/or other network services in a fast and efficient manner and in such a way as to increase bandwidth utilization and power efficiency.
A multi-frequency network (MFN) is a network in which multiple radio frequencies (RFs) (or RF channels) are used to transmit media content. One type of MFN is a horizontal multi-frequency network (HMFN) where a distribution waveform is transmitted over different RF channels in different local areas. The same or different content may be transmitted as part of a distribution waveform carried over different RF channels in such local areas. Another type of MFN is a vertical multi-frequency network (MFN) in which multiple radio frequency (RF) channels are used in a given local area to transmit independent distribution waveforms with an aim to increase the capacity of the network (in terms of the ability to deliver more content to a device/end user). An MFN deployment may also consist of VMFN in certain areas and HMFN in certain other areas.
In a typical VMFN, a local area operations infrastructure (LOI) comprises transmitting sites that operate to transmit multiple distribution waveforms over multiple RF channels in a selected geographic area. Each distribution waveform may comprise one or more content flows that can be selected at a receiving device for rendering. Adjacent LOIs may utilize the same or different RF channels.
Unfortunately, conventional systems may perform spurious RF channel switches when a receiving device attempts to switch from a first RF channel (RF1) to a second RF channel (RF2) in a given LOI. For example, when a device attempts to switch to the second RF channel to receive a desired content flow, the device may unintentionally switch to a neighboring LOI that also transmits content on the second RF channel, but that content is different from the content transmitted in the current LOI. If the device is in an area where the two LOIs provide overlapping coverage, the second RF channel from the neighboring LOI may be received with higher power than the second RF channel transmitted in the current LOI. As a result, a spurious RF channel switch may occur because the device may attempt to process the distribution waveform that it received with the higher power from the neighboring LOI. However, if this happens, the device will be unable to find the desired content flow on that distribution waveform because the neighboring LOI transmits different content on the second RF channel than what is transmitted in the current LOI.
Therefore, it would be desirable to have a system that operates to reduce or eliminate spurious RF channel switches and thereby facilitate fast RF channel switching capabilities in a multi-frequency network.